This invention relates to optical devices and, more particularly, to optical devices involving lasers and modulators.
External modulation has been used in some semiconductor laser systems where one or a few edge emitting lasers were used in a linear arrangement. Single channel use of modulators with edge emitting lasers in a package is also therefore possible. However, presently, two dimensional arrays of edge emitting semiconductor lasers are not in the prior art, hence integration of modulators with such lasers is not possible in the prior art. In addition, modulators that can be integrated with arrays of vertical emitting format lasers, particularly, vertical emitting cavity, distributed feedback (DFB) lasers and distributed Bragg reflector (DBR) lasers, are not available in the prior art.
As shown in FIG. 1, we integrate arrays of vertical cavity modulators 100 on top of arrays of lasers 102 which are integrated on top of electronics 104 (one or more chips). By employing the teachings of the invention, we create large laser arrays in which each of the lasers can be operated at constant light output and the output can be switched on an off, very rapidly, via external modulation through integration of the modulator array on top of the laser array. As a result, we can accomplish a number of advantages including switching lasers in a two-dimensional semiconductor laser array at rates both below, and in excess of, 10 Gb/s.
The advantages and features described herein are a few of the many advantages and features available from representative embodiments and are presented only to assist in understanding the invention. It should be understood that they are not to be considered limitations on the invention as defined by the claims, or limitations on equivalents to the claims. For instance, some of these advantages are mutually contradictory, in that they cannot be simultaneously present in a single embodiment. Similarly, some advantages are applicable to one aspect of the invention, and inapplicable to others. Thus, this summary of features and advantages should not be considered dispositive in determining equivalence. Additional features and advantages of the invention will become apparent in the following description, from the drawings, and from the claims.